I have the Sapphire 830 and love it. It has a 10 in harp space, I measured it. No lever to lift the foot.
It will automatically raise and lower the foot just a little when in needle down. Love that feature.
Have had it for years with no problems and I use plain old Coats and Clark thread with no problems.
The only problem is if you are trying to sew over lumps like hems, it dosnt like it and will just sit in one spot.
For quilting it is great.